Gun sight



P 1959 G- METALLO 2,902,764

GUN SIGHT Filed Dec. '30, 1955 3 Sheets-Sheet 1 J E55 ,19 41 40 40a 224 62 o 229 47 J 227 a 22 63a 231a F19 j G. METALLO Sept. 8, 1959 GUN SIGHT 3 sheets-sheet 2 Filed Dec. 30, 1955 P 3, 1959 G. METALLO 2,902,764

' GUN SIGHT Filed Dec. so, 1955 3 sheets sheet 3 United States Patent Q .3"

GUN SIGHT Gelsomino Metallo, Rome, Italy Application December 30, 1955, Serial No. 556,606

Claims priority, application Italy December '31, 1954 12 Claims. (Cl. 33-49) This invention relates to gun sights and is particularly concerned with a gun sight which has been specially devised for firing against aerial targets but is also available for land and naval targets, either in motion or stationary.

With respect to the possibility of application of the invention, the word gun or weapon is to be intended in a very wide meaning, also including means for throwing missiles of various kinds, e.g. rocket launchers.

At present, one employs either antiaircraft directors which are very complicated and expensive, or very simple aiming devices which are however unsatisfactory as they do not solve the problem of the continuous correction and moreover are difllcult to use by the gunner.

This invention solves the problem of continuously determining the deflection angle and its plane, although using means which are simple and very easy to operate. The gun sight according to the invention is relatively inexpensive, which allows for the utilization thereof also for small caliber weapons.

Before describing the gun sight according to this invention, it must be said that in the specification and claims, for the sake of simplicity, the allowances for the gravity drop and drift of the projectile are considered as null when reference is made to the relationship of the sight elements to the gun axis. Anyway, said allowances may be taken into account considering an average value thereof and displacing the axis of the gun sight with respect to the weapon axis in accordance with said average values.

It is known that the deflection angle depends on the angle the direction of movement of the target makes with the line of sight, hence with the adequate direction of the weapon axis at the shooting time, the target speed, the target range, hence the mean speed of the projectile corresponding to said range.

With the above said in view, the gun sight according to the invention, generally speaking comprises: an arrow which may be placed by hand in a parallel direction to the target course by means of two rotations thereof about two cardanic axes, the primary one being parallel to the weapon axis and the other being at right angles therewith, whereby the rotation of the arrow about the primary axis introduces in the gun sight the plane of the deflection angle, whilst the arrow rotation about the secondary axis introduces in the gun sight the required impact angle; a member which is driven in rotation by the arrow rotating about its secondary axis, said member being capable of introducing the target speed and the mean speed of the projectile corresponding to the target range, said 'member being either a three dimensional cam each cross section of which corresponds to a couple of values of speed and range of the target, the radii thereof being calculated for each impact angle taking into account the variation of the target range during the time of flight of the projectile, or a material vector parallel to the arrow, whose length may be adjusted in relation with the target speed and whose origin may be brought to a position corresponding to the actual range of the target; an optical system comprising a collimator producing a tele- Patented Sept. 8, 1959 scopic mark and a semi-transparent mirror which reflects the mark image to the gunners eye and allows for the direct vision of the target in transparenc'e; a transmis= sion from the said member fastened to the secondary rotation axis of the arrow to the optical system to deflect the sight line (identified by the mark) from the firing line (weapon axis) by the proper angle, depending on the cinematic conditions; and a transmission from the primary rotation axis of the arrow to the optical system to give the proper laying to the deflection angle.

This invention will be better explained with reference to the accompanying drawings which show, by way of examples, some embodiments of the invention.

In the drawings, which are schematic:

Fig. 1 is a perspective view, with parts in section and parts omitted, of a first embodiment.

Fig. 2 is a similar perspective View of a second embodiment.

Fig. 3a is a substantially vertical section of a third embodiment, and

Fig. 3b represents a modification of certain parts of the embodiment of Fig. 3a.

Fig. 4 is a substantially vertical section of a fourth embodiment.

Fig. 5 is a view with parts broken away and parts omitted, of a calculator triangle which may be employed in certain embodiments of the invention.

Fig. 6 is a section on an enlarged scale of the principal elements of the calculator triangle.

In the embodiment shown in Fig. 1, the stationary case for the sight, which case is fastened to the weapon, is designated by reference numeral 11. In said case a box 12 is mounted in such a way that it may rotate about axis XX which is parallel to the weapon axis. A shaft 13, whose geometrical axis is indicated by Y-Y, extends through box 12 and is rotatably supported thereby. To one end of shaft 13 a button 14 is fastened, which serves for turning said shaft, to the other end of which an arrow 15 is fastened. Moreover, inside box 12 a three dimensional cam 16 is keyed to shaft 13. Axes XX and Y--Y intersect at right angles, i.e. they are cardanic axes, XX being the primary axis and Y-Y the secondary axis. The different cross-sections of cam 16 are each calculated for a given pair of values of speed of target and actual range of target, taking also into account the future target range.

It is not deemed necessary to explain the mathematical and/or graphic method or methods for designing the cam on the basis of the cinematical conditions and the transmission ratio from cam follower to catoptric collimator, as said method or methods belong to the common knowledge of those skilled in the art.

The cam follower, designated by reference numeral 17, is carried by arm 18 which is capable of gliding along shaft 19, said shaft and arm 18 being however positively connected for rotary movements.

In order to displace arm 18 along shaft 19, consequently to displace follower 17 along cam 16 for the purpose of selecting the cross-section which corresponds to the actual target speed and range, a two-arm lever is provided, whose arm 20 is situated within box 12, whilst its arm 21, which is shown broken away, extends outwardly of box 12 and is provided with a handle.

Am 21 is equipped with a spring stop 22, which may be selectively brought into engagement with any one of a number holes pierced in disc 23. Said disc may assume on box 12 a number of different positions (five in the example shown), each corresponding to a given target speed, and may be blocked in the selected position by means of a hand operated latch, which is not seen in the figure. The adjustment of disc 23 is eifected 3 when the target is identified and its speed is accordingly known.

For each of the different positions of disc 23, a number of holes are provided on said disc (three in the example shown), each corresponding to a given target range. Spring stop 22 yields when a suflicient force is applied to arm 21, so that the position of said lever may be changed by the operator as the target range changes during the shooting.

The above described arrangement (and the analogous ones in the other embodiments to be described) corresponds to the normal conditions of firing, wherein the target speed may be considered as constant in each case, whilst the target range changes.

The end of arm 20 is shaped as a fork 25 which engages arm 18 of follower 17, so that the angular displacements of lever 20-21 cause a translation of arm 18 along shaft 19, hence a displacement of follower 17 along cam 16.

An arm 26 terminating with a toothed sector 27 is fastened to or integral with shaft 19. Toothed sector 27 meshes with pinion 28 which also meshes with toothed sector 30 fastened to shaft 31 journalled in brackets 32 integral with box 12.

The axes of shaft 13, shaft 19, pinion 28, shaft 31 are parallel to one another.

From shaft 31, opposite to sector 30 a rod 33 extends, which is rotatably received in sleeve 34.

Said sleeve 34 is integral with or fastened to a yoke 35 whose branches are pivoted at 36 on a frame or structure 37. Structure 37 is pivoted at 38 to the stationary support or case 11. The geometrical axis of pivots 36 and the geometrical axis of pivot 38 intersect at right angles, i.e. they are the axes of a cardanic assemblage, the center of which lies on axis X-X. Also integral with or fastened to yoke 35 there is an arm 39 having an antifrictional roller 40 at its free end, said roller bearing on the end of a lever 41 which is integral with or fastened to a shaft 42. Levers 39 and 41 are urged toward each other by a tension spring 40a. Shaft 42 is rockably supported at right angles with lever 41 and its geometrical axis intersects the circumference described by the rotation axis of roller 40. Frame or structure 37 has a tubular extension 43 rotatably received in a sleeve or bush 44 integral with the bottom of case or stationary support 11 for the gun sight. The rotation axis of tubular extension 43 is in alignment with the axis of pivot 38.

A stirrup 45 is fastened to tubular extension 43, and on the sides of the stirrup 45 is the semi-transparent mirror 47 pivoted on pivots 46, the axis of rotation of semitransparent mirror 47 being parallel to shaft 42.

The rotation of arrow 15 about axes XX and Y-Y, respectively, cause in general a rotation of frame or structure carrying mirror 47, hence of stirrup 45, aibout the common axis of pivot 38 and tubular extension 43, and a swinging movement of lever 39.

Any swinging movement of lever 39 causes a swinging movement of half amplitude of lever 41. Shaft 42 projects from the gun sight case and through crank arm 48, link 49 and crank arm 48a, which is fastened to the semi-transparent mirror 47, integrally transmits to said mirror the swinging movements of lever 41. In fact, crank arms 48 and 48a are equal and parallel to each other, and link 49 is equal and parallel to the distance from the axis of shaft 42 to the axis of pivots 46, as measured along the geometrical axis of pivot 38 and tubular extension 43.

Inasmuch as the amplitude of swinging movement of lever 41, hence of semi-transparent mirror 47, is equal to half the amplitude of the corresponding swinging movement of lever 39, the deflections about an horizontal axis of the beam of light proceeding from the collimator which is to be described hereinafter and reflected by semi-transparent mirror 47 are of the same amplitude as the corresponding swinging movement of lever 3 The collimator 51, which is fastened to a rigid extension 52 of the gun sight case or support 11, comprises two lamps 53, 53 each located in one focus of an elliptic reflector 54, so that either is capable of causing a beam of light to be projected through two reticules 55 and 56. If one lamp burns out, the other will be available.

Reticule 56 is stationary, reticule 55 may be rotated in contact with reticule 56, owing to the provision of an outwardly projecting lever or handle 57.

Both reticules are generally obscure, but each presents a series of transparent elliptical lines.

The two series of transparent elliptical lines on the two reticules are equal to each other but do not register when the reticules are in the position shown in the drawing, that is when the gun sight is in working condition. By rotating reticule 55, however, the two series of transparent elliptical lines may be caused to register for the purpose which is to be explained hereinafter. Reticule 55 is provided with a central transparent area of a very reduced diameter, whilst reticule 56 is provided with a small central transparent cross. Due to the above described arrangement, until reticules 55 and 56 are in the position shown, only the beams of rays passing through the central cross of reticule 56 and the intersections of the elliptical lines may be reflected by the stationary mirror 58 to the lens 59 and reach the gunners eye after reflection on the semi-transparent mirror 47.

Lacking the artificial light, by removing cover 60' together with elliptic mirror 54 (although said parts are not represented as removable in the drawing, for the sake of simplicity), the gun sight may still be used provided the natural light be sufliciently bright.

It will now be explained why two reticules each with a series of transparent elliptical lines have been provided.

When an operator is available for manipulating arrow 15, then it is convenient for the gunner to see only the central cross and the punctiform images of the intersections of the elliptical lines. However, if such an operator is not available, arrow 15 is adjusted in a parallel direction to the weapon axis, so that the cross indicates the line of aim, reticule 55 is brought to the position in which its transparent elliptical lines register with those of reticule 56, and the gunner may utilize said elliptical lines in the same way as with a conventional catoptrie collimator in which the evaluation of the necessary aiming allowance is made by the gunner with the help of the elliptical lines.

To the sides of stirrup 45 which support the pivots 46 for the semi-transparent mirror 47, a frame 61 is fastened on which a reticule 62 is rotatably mounted about pivot 62a. Moreover a peep-sight 63 is provided which may assume either a position, not shown, outside the field of vision of the gunner, or the position shown in the drawing, whereby the laying of the weapon is possible even when the catoptric collimator is unavailable, e.g. due to the lack of light either artificial or solar. Peep-sight 63 is carried by a structure 63a rotatably mounted on pivots 46, so that it can be rotated in the direction of the arrows. When structure 63a is in the position shown, it follows the movements of members 48a, due to suitable connections (not shown).

It is to be noted that in all the embodiments of the invention the arrangement of the parts, and particularly the means of transmitting the rotations of the arrow to the optical system is such that the arrow is placed at a higher level than the gunners head, so that the arrow may by manipulated without interfering with the gunners sight.

In the embodiment shown in Fig. 2 the stationary supporting case of the gun sight, fastened to the gun, is designated by reference numeral 111.

A unit 112 is rotatably supported by case 111, the rotation axis X-X being parallel to the weapon axis and representing the primary axis of the cardanic mounting of arfows 115. Said arrows are fastened to shaft 114 whose axis is the secondary axis of the cardanic mounting. On shaft 114 a cam 116 is mounted in such a way that it may slide along the shaft but must follow the rotary movements thereof. The displacements of cam 116 in an axial direction along shaft 114 are eflected by rotating drum 117 rigidly connected to pinion 118 which meshes with rack 119. Rack 119 is a part of a frame or structure 120 which drags cam 116 in its translation movements without interfering with the rotation movements of the cam. The graduations for the speed of the target are provided on a track 117a and the gun sight is adjusted for the target speed by displacing slider 11712 on track 117a. Slider 117b carries an indicator and the graduations for the range of the target are provided on drum 117 in such a way that the gun sight is adjusted for the target range by rotating drum 117 to bring the point of said indicator on the proper graduation. Said rotation of drum 117 brings about such a displacement of cam 116 in an axial direction that the cam follower 121 registers with the cross section of the cam which corresponds to the couple of actual values of speed and range of the target.

In a preferred arrangement, the graduation lines for the target ranges are deeply engraved on the drum and the indicator point resiliently enters them so that the operator may change the adjustment for the target range without looking at the drum.

Follower 121 is carried by a two-arm lever pivoted at 122, whose end opposite to said follower is formed as a toothed sector 123. The axis of pivot 122 is parallel to axis Y-Y. Toothed sector 123 meshes with toothed sector 124 fastened to a spindle 125 journalled in brackets 126 integral with or fastened to box 112. Toothed sector 124 is integral with or fastened to a rod shaped tail 124a which is rotatably received in a sleeve 127. Spindle 125 is parallel to axis YY.

Sleeve 127' is supported by a yoke 128 which is pivoted on an axis ZZ to a frame 129. Frame 129 may rotate about an axis WW which passes through pivot 130 and through the center of plate 131 rotatably supported by the apertured bottom of stationary case 111.

Axis ZZ passing through the pivots for the swinging .movements of yoke 128 and axis WW intersect at right angles, and their intersection lies on axis XX. In other words, axes WW and ZZ are the axes of a cardanic contrivance.

A toothed sector 132 is integral with one leg of yoke 128 and meshes with a bevel gear 133. Shaft 134 fastened to bevel gear 133 is also fastened to a second bevel gear 135 which meshes with a toothed sector 136.

Toothed sector 136 is fastened to a catoptric collimator designated as a whole by reference numeral 137, which may swing about two pivots 138, only one of which may be seen in the drawing.

The geometrical axis of said pivots 138 is parallel to axis ZZ.

The catoptric collimator 137 comprises the reflector, the lamp, the reticule, the lens and the semi-transparent mirror to which no reference numerals have been applied.

By means of the gearing 132133, 135136, the swinging movements of sector 132 are translated into corresponding swinging of collimator 137 about pivots 138.

Consequently, the rotations of arrows 115 about their cardanic axes are translated into a rotation of collimator 137 about axis WW and a swinging movement thereof about pivots 138.

The parts are so proportioned that the above mentioned movements of the collimator cause the proper deflection of the light beam proceeding from the central cross of the reticule.

In the embodiment shown in Fig. 3a, XX is the rotation axis of box 212 and Y is the projection of the 6 rotation axis of cam 216, which is arranged for axial displacements as in the embodiment of Fig. 2.

The cam follower 217 is carried by lever 218 pivoted at 219 and on said lever 218 one end of thrust-rod 220 bears, the other end of which bears on one arm of a bell lever 22'1 pivoted at 222, the other arm of which acts on a thrust-rod 223. Said rod bears on a lever 224. A depending extension on lever 224 has its free end shaped as a fork 225, which engages a lamp supporting carriage 226. Said carriage is slidably mounted on track 227 which is parallel to a diameter of the focal plane of lens 228.

Spring 229 acts to keep the cam follower 217 pressed on cam 216.

Rotations of casing 212 about axis XX, which is parallel to the weapon axis, are transmitted to lamp support 231 by means of a couple of bevel gears 230.

Accordingly the lamp, which is obscured with the exception of a transparent central cross and eventually a reticule, is imparted a rotary motion about axis WW and a translation motion along the diametrical track 227.

A semi-transparent mirror 232 reflects the image of the above mentioned cross to the gunners eye in a direction which is inclined to the weapon axis by the proper deflection angle in the proper plane.

Fig. 3b shows a modification of the preceding embodiment. Therein, thrust-rod 22*3b acts on a parallelogram designated as a whole by 233, so that the axial displacements of the thrust-rod bring about swinging movements of collimator 234 about axis 235. As a matter of convenience axis 235 should pass through the center of gravity of collimator 234. Member 237 of parallelogram 233 is rigidly fastened to depending box 231a (corresponding to depending box 231 in Fig. 3a), and collimator 234 is rigidly fastened to parallelogram member 238 to swing therewith.

In this embodiment, lens 236 rotates about axis WW and about axis 235. In the focal plane of the lens is placed a reticule with a central transparent cross, and the above mentioned rotations cause the light beam from the cross to assume a direction corresponding to the proper sight line.

In the embodiment shown in Fig. 4, wherein various parts have been omitted, on cam 316 a follower 317 bears, which is carried by a lever 318 pivoted at 318a. Said lever acts on a thrust-rod 319 which presses on a body 320. Said body may rotate about a spindle 321 which is fastened to an extension, not shown, of cam carrying box 312 in a parallel relationship to the arrow shaft and passes through the center of a cardanic arrangement whose primary and secondary axes are designated by WW and ZZ respectively. The intersection of said axes lies on the primary axis XX of the cardanic mounting of the arrow.

A rod 322 integral with body 320 is rotatably received in a sleeve 323 integral with or fastened to a yoke 324, which may rotate about the secondary axis ZZ of the above mentioned cardanic arrangement.

The rotations of cam 316 about its own axis Y-Y and of the whole box 312 about axis XX cause in general two rotations of axes WW and ZZ. Rotation of axis WW is integrally transmitted in an azimuthal direction to another yoke, designated as a whole by reference numeral 325, which is swingably supported by yoke 324 about the secondary axis ZZ. A stem 325a, integral with yoke 325, extends downwardly along the middle line thereof and supports a depending stirrup 32512. A collimator, designated as a whole by reference numeral 326, is swingably mounted between the branches of stirrup 325b, the swinging axis being parallel to said secondary axis ZZ. The rotation of the secondary axis ZZ is transmitted to the collimator in a zenithal direction through an articulated parallelogram designated as a whole by reference numeral 327. The semi-transparent mirror 328 is rigidly fastened to the collimator.

Figures and 6 show how a calculator triangle may be substituted for the cam and associated parts employed in the embodiment of Fig. 1 or 2, or similar embodiments.

In such a calculator triangle, the length of the first side is adjustable for the target speed, the length of the second side is adjustable for the target range, the angle be tween the above mentioned sides is adjustable for the impact angle. The third side is self-adjusting and the angle opposite to the first side is the aiming angle to be transmitted to the collimator.

The first named side of the triangle, which is parallel to the arrow, is the material vector mentioned in the introductory part of this specification.

Referring now to the drawings, in the stationary case 411 is rotatably mounted a box 412, the rotation axis of said box being the primary axis of the cardanic mounting of arrow 425. In box 412 a two-arm lever 414 is mounted for swinging movements about pivot 413. This latter is one of the axes of a second cardanic arrangement and corresponds to shaft 31 in Fig. 1, or to shaft 125 in Fig. 2.

One arm of lever 414 is provided at its end with an antifriction roller 415 which may run on a circularly arcuated track 416. The other arm of lever 414 is rotatably received in a sleeve 434. Sleeve 434 corresponds to sleeve 34 of the embodiment shown in Fig. 1 or to sleeve 127 of the embodiment shown in Fig. 2. Therefore the mounting of sleeve 434 and the remaining parts of the gun sight are not shown or described, as they may be similar to those described with reference either to Figures 1 or 2. More generally, the calculator triangle as shown in Figures 5 and 6 may be employed in any embodiment of this invention wherein the transmission of the two rotations from the arrow to the optical system is effected by means including a second cardanic arrangement.

On lever 414 a slider 417 may freely slide and a rack 418 is pivoted at 417a thereon. The portion of lever 414 between the center of pivot 413 and the center of pivot 417a is the self-adjusting side of the triangle.

Rack 418 is the first side of the triangle, i.e. the side adjustable for the target speed. Rack 418 is slidably received by a guiding track 419 which is fastened to a frame 420 in a parallel relationship to arrow 425, which is rigidly connected to said frame. Rack 418 meshes with pinion 421 provided with a hollow hub 422 to which a disc 423 (omitted in Fig. 5) is fastened. Accordingly, rotation of disc 423 relative to arrow 425 causes a longitudinal displacement of rack 418 along its guiding track, hence a variation of the length of said rack as measured from the center of pivot 417a to the pinion axis, which is also the secondary axis of the cardanic mounting of arrow 425. The graduations for the target speed are provided on disc 423.

Stem 424, which rigidly connects arrow 425 with frame 420, is of a circular cross section and passes through the hollow hub 422.

When adjusting the length of rack 418, the disc 423 must be free to rotate about stem 424 of arrow 425, but when the gun sight is in operating condition arrow 425 and disc 423 must be fastened together in the proper position depending on the target speed. This is obtained by providing a hand actuated stop or latch 426 on the arrow and a series of holes on the outer face of disc 423, each hole corresponding to a determined target speed, and causing the stop or latch to engage the proper hole in each case.

Hollow hub 422 extends through a long slot 427 in a lever 428 pivoted on a stationary pivot 429. Moreover said hollow hub is also slidable in a slot 430 provided in the wall of box 412 and aligned with the center of pivot 413. Notches are provided in one side of slot 430, each corresponding to a given range of the tar-get. By moving lever 428 by hand, the gun sight may be adjusted for the target range; in fact the side of the triangle adjustable for the target range lies on the line which passes through the center of pivot 413 and the middle longitudinal line of slot 430.

The operation of the above described calculator triangle is as follows. The target speed being known, the value thereof is introduced by rotating disc 423, after having loosened arrow 425, as described. The adjustment for the target speed having been effected, arrow 425 and disc 423 are again fastened together, and the gun sight is adjusted for the range of the target by moving lever 428 to its proper position.

Arrow 425 is then brought to and afterwards maintained in a parallel position to the target path, to introduce in the gun sight the impact angle on the proper plane.

The manipulation of the arrow causes in general a rotation of box 412 about axis X--X and a swinging movement of sleeve 434. The above mentioned rotation and swinging movement are transmitted to the optical system.

As the target range changes, lever 428 is accordingly moved by hand.

Of course the parts of the triangle are so proportioned that the angle opposite the rack is the proper deflection angle corresponding to the cinematic conditions.

All the above described embodiments are based on the same inventive idea, i.e. to introduce in a gun sight the proper plane of the deflection angle by means of a rotation of an arrow about the principal axis of a cardanic mounting of said arrow, and to transmit said rotation to an optical system comprising a collimator and a semi-transparent mirror, in order to place in the proper plane the telescopic mark supplied by the collimator, to introduce the impact angle by means of a rotation of said arrow about the secondary axis of its cardanic mounting and to transmit the rotation to the optical system by means of a calculating transmission which takes into account the speed and the range of the target and accordingly causes the proper deflection of the virtual line aim.

In the embodiments comprising a three dimensional cam of the kind described, although the actual range of the target is introduced, the mean speed of the projectile corresponding to the future range of the target is taken into account.

In the embodiments which employ a calculator triangle, the mean speed of the projectile corresponding to the actual target range is considered, and not that corresponding to the future range.

The invention also comprises the possible combinations of features described with reference to the embodiments shown.

Inasmuch as the consideration of the above specification and accompanying drawings may suggest to those skilled in the art different modifications and changes which fall within the scope of the invention, it is to be understood that this specification and accompanying drawings are not to be construed in a limiting sense.

What I claim is:

1. A gun sight comprising, in combination, an arrow to be located and maintained in a parallel relationship to a target course by means of rotation thereof about a primary cardanic axis and about a secondary cardanic axis; a shaft that is fastened to the arrow and that registers with the secondary cardanic axis; a box which -ro tatably supports the arrow shaft and which is mounted for rotation about the primary cardanic axis; a supporting case for said box that is fastened to the weapon, the axis of rotation of the box being in parallel relationship with the axis of the weapon, so that the rotation of the box about the primary cardanic axis introduces in the gun sight the plane of the deflection angle and the rotation of the arrow and its shaft about the secondary cardanic axis introduces in the gun sight the required impact angle when the target is being tracked; a member which is rotatably driven by the arrow shaft and which is adjustable for the couple of values of target speed and target range; a device supplying a sight line or aiming line to the gunners eye; transmission means from the arrow shaft to at least one member of the device which supplies the sight line, to transform the impact angle into the proper deflection angle, depending on the cinematic conditions, said transmission means including the said member rotatably driven by the arrow shaft as the true calculating element; and transmission means from the box which rotates about the primary cardanic axis to at least one member of the device which supplies the sight line, to give the proper laying to the deflection angle; the said transmission means making an angular deviation to allow for the device supplying the sight line to be placed at a lower level than the arrow.

2. A gun sight according to claim 1, wherein the transmission means from the arrow shaft to the device supplying the sight line comprises a three dimensional cam carried by the shaft and rotating therewith and a cam follower, the outline of each cross section of the cam being calculated for one given couple of values of speed and range of the target with the radii thereof calculated for each impact angle taking into account the variation of the target range during the time of flight of the projectile, hand operated means being provided to cause a relative displacement of cam and follower in the axial direction of the arrow shaft to render operative the proper cross section of the cam in each case.

3. A gun sight according to claim 2, wherein the cam is fastened to the arrow shaft and the follower is carried by an arm mounted for displacement in the axial direction of the cam, the hand operated means for dis placing said arm being a lever provided with means for a first adjustment for the target speed and a second adjustment for the target range which is variable during the shooting.

4. A gun sight according to claim 2, wherein the cam is positively connected to the arrow shaft for rotating therewith but is slidably mounted thereon, the hand operated means for displacing the cam comprising a rack connected to the cam for translation movements, a pinion meshing with said rack, a driven drum for said pinion, said drum being provided with different scales, each scale corresponding to one target speed and presenting graduations for various target ranges, and an indicator which may be displaced in a longitudinal direction along the drum to select the proper scale, while the point thereof is to be brought on the proper graduation for the target range by rotating the drum.

5. A gun sight according to claim 2, in which the device which supplies the line of sight or aiming line comprises a collimator producing a telescopic mark and a semi-transparent mirror which reflects the mark image to the gunners eye and allows for the direct vision of the target in transparence, and wherein the transmission means leading to said device comprise the cam follower, a two-arm lever carrying on one arm said cam follower, a first toothed sector on the other arm of said two-arm lever, a pinion meshing with said first toothed sector and located with its aims parallel to the arrow shaft, a second toothed sector meshing with said pinion, a second two-arm lever carrying said second toothed sector and arranged with its swinging pivot in a parallel relationship to the arrow shaft, brackets carried by said rotatable box and swingably supporting the pivot of the second two-arm lever the other arm.of which is shaped as a rod, a sleeve rotatably receiving said rod, a yoke on said sleeve, a frame pivotally supporting said yoke and rotatably supported by the stationary case, -a dependent stirrup fastened to said frame, bearings on the stirrup for pivotally supporting the semi-transparent mirror and arranged on a line which is parallel to the swinging axis of the yoke, the swinging axis of the yoke and the axis of rotation of the frame intersecting at right angles on the axis of rotation of said box, and means being provided to halve the swinging movements of the yoke and 10 transmit said halved swinging movements to the semitransparent mirror, so that the virtual aiming line supplied by the collimator, which is stationary, and the semitransparent mirror is rotated in accordance with the rotation of the said box and is deflected in accordance with the swinging movements of said yoke.

6. A gun sight according to claim 2, in which the device which supplies the line of sight or aiming line comprises a collimator producing a telescopic mark and a semitransparent mirror which reflects the mark image to the gunners eye and allows for the direct vision of the target in transparence, said collimator and mirror being rigidly connected, and wherein the transmission means leading to said device comprise a two-arm lever carrying on one arm said cam follower, a first toothed sector on the other arm of said two-arm lever, a second toothed sector meshing with the first sector, a second two-arm lever carrying at one end said second toothed sector and having its swinging pivot parallel to the arrow shaft, brackets on said rotating box and rotatably supporting said swinging pivot of the second two-arm lever the other arm of which is shaped as a rod, a sleeve rotatably receiving said rod, a yoke on said sleeve, a frame pivotally supporting said yoke and rotatably supported by the stationary case, a depending extension of said frame, bearings on said depending extension for pivotally supporting the collimator and the semi-transparent mirror and located on a line which is parallel to the swinging axis of the yoke, and gearing connecting said yoke to the collimator to transmit the swinging movements of said yoke to the collimator, so that the virtual aiming line is brought to the proper plane by the rotation of the collimator and the semi-transparent mirror and is deflected by the proper deflection angle by the swinging of the collimator and semi-transparent mirror.

7. A gun sight as claimed in claim 2, in which the device which supplies the line of sight or aiming line includes a lens and a semi-transparent mirror fastened to the gun sight case, a depending box rotatably supported by said case, a track arranged on a diameter of said depending box, a lamp and a lamp support in the form of a carriage slidably mounted on said track, and wherein one transmission means acting on said device comprises a bevel gearing drivably connecting the box to rotate the depending box to determine the proper plane for the deflection angle, and the other transmission means comprises the cam follower, a swinging lever carrying said cam follower and a linkage drivably connecting said swinging lever to the lamp supporting carriage, so that the rotation movement of the arrow shaft is transformed into a sliding movement of the carriage along its track in accordance with the proper deflection angle.

8. A gun sight as claimed in claim 2, in which the device which sup-plies the line of sight or aiming line comprises a collimator and a depending box rotatably supported by the gun sight case and swingably supporting the collimator, and wherein one transmission means acting on said device comprises bevel gearing drivably connecting the box to rotate said depending box to determine the proper plane for the deflection angle and the other transmission means comprises the cam follower, an articulated parallelogram having one side stationary withrespect to the depending box, one side rigidly connected to the collimator and swingable therewith, and a linkage drivably connecting another side of the parallelogramto said cam follower, so that the rotation movement of the arrow shaft is transformed into a swinging movement of the collimator corresponding to the proper deflectionx angle.

9. A gun sight according to claim 2, in which thedevice which supplies the line of sight or aiming line comprises a collimator and a semi-transparent mirror fastened together, and wherein the transmission means: acting on said device comprise the cam follower, a swing-- ing lever supporting the cam follower, a thrust rod, aa

swinging body acted upon by the thrust rod and having a swinging spindle supported by the rotatable box in a parallel relationship to the arrow shaft with the spindle axis intersecting the axis of rotation of the box, a rodlike extension of said body, a sleeve which rotatably receives said rod-like extension, a yoke on said sleeve and mounted for swinging movement about an axis which intersects at right angles the spindle axis, so that the spindle axis and the yoke swinging axis are the primary and secondary axes, respectively, of a cardanic arrangement, a depending second yoke swingably supported by the first yoke about the secondary axis of said cardanic arrangement, a stirrup fastened to said second yoke and swingably supporting the collimator, and a linkage in the form of an articulated parallelogram connecting said sleeve to said collimator, with the result that the rotation about the primary axis of said cardanic arrangement is directly transmitted in an azimuthal direction to the stirrup, and the swinging movement about the secondary axis of the cardanic arrangement is transmitted in a zenithal direction to the collimator.

10. A gun sight according to claim 1, wherein the transmission means from the arrow shaft to the device which supplies the line of sight or aiming line comprises a calculator triangle one apex of which is a fixed pivot situated inside the box which rotates about the primary cardanic axis of the arrow and is parallel to the secondary axis thereof, the structural parts of the triangle being one arm of a two-arm lever pivoted on said fixed pivot, a slider mounted on said lever arm and delimiting one self-adjusting side of the triangle, a rack pivoted on said slider, a frame having a guiding track slidably to receive said rack and rigidly supporting the arrow in a parallel relationship with the rack, a pinion meshing with the rack and having a hollow hub concentrically receiving the arrow shaft and integral with an actuating disc the rotation of which causes a relative displacement of the rack and frame and adjusts the triangle for the target speed, a slot in the wall of the rotatable 'box in alignment with said fixed pivot, a hand actuated lever slidably engaging said hollow hub for displacing it in the rotatable box slot to adjust the triangle for the target range, the transmission means further comprising the second arm of the said two-arm lever, means transmitting the rotation of the rotatable box to the device which supplies the line of sight to set this line on the proper plane, and means which transmit the swinging movement of the second arm of the two-arm lever to said device to deflect the line of sight by the proper angle in said plane.

11. A gun sight as claimed in claim 1, wherein the device which supplies the line of the sight or aiming line includes a collimator comprising an elliptical reflector and two lamps each in one focus of the reflector, the collimator casing has an aperture provided with a cover to which the reflector is fastened to allow for the operation with natural light when said cover is displaced, two reticules are provided in contact with each other, the one nearer to the lamps presenting a central transparent area of a very reduced diameter and the other presenting a central transparent cross, the remaining portions of both reticules being obscure with the exception of two equal series of transparent elliptical lines, one series on each reticule, and one of the reticules being rotatably mounted to bring its elliptical lines in or out of coincidence with the lines of the other reticule.

12. A gun sight according to claim 1, wherein the device which supplies the line of sight or aiming line includes a collimator the support of which further supports an auxiliary aiming device consisting of a reticule and a peep-sight, both pivotally mounted to be brought in or out of the gunners field of vision as required.

References Cited in the file of this patent UNITED STATES PATENTS 2,183,530 Alkan Dec. 19, 1939 2.237,613 Petschenig Apr. 8, 1941 2,384,036 Klemperer et a1. Sept. 4, 1945 2,405,383 Wackett Aug. 6, 1946 2,517,779 Flint Aug. 8, 1950 2,547,654 Moore Apr. 3, 1951 

